1. Field of the Invention
The present invention relates to a digital camera system and a digital camera in which a lens unit having a taking lens and a solid state imaging device is removably attached to a camera body.
2. Description Related to the Prior Art
A digital camera is widely used, and includes a solid state imaging device such as a CCD image sensor for capturing an image to store data of the image to a data storage. A digital camera system in which a lens unit having a taking lens and a solid state imaging device is removably attached to a camera body is also known (for example, Japanese patent laid-open publication Nos. 10-191122, 10-233953, 2000-50138 and 2000-106640).
In digital camera systems disclosed in the above publications, a desired lens unit is selected from among various lens units with different focal lengths of taking lens or with different types of solid state imaging device, and the selected lens unit is attached to a camera body.
Moreover, in the digital camera systems disclosed in JP-A 10-191122 and JP-A 2000-50138, the camera body controls timing for activating each part of the digital camera system, and the lens unit works in accordance with a timing signal generated by the camera body. However, a suitable timing signal varies widely according to the type of the solid state imaging device. It is therefore difficult to provide versatility with the camera body to be able to drive various kinds of lens units.
In the digital camera system disclosed in JP-A 10-233953, the problem like the above publications have does not arise since the lens unit has a built-in timing generator. However, synchronization of operations between the lens unit and the camera body is not taken into account. The synchronization of the same is not considered in JP-A 2000-106640 as well.